As is well known in the art, spinning frames are used to build yarn packages on bobbins carried on rotating spindles of the spinning frame, such yarn being fed to the bobbins by a ring rail reciprocating along the axes of the bobbins and spindles. After the yarn package is built on the bobbin, the reciprocating ring rail is lowered to a position beneath the lowest extent of bobbins to cause a plurality of yarn wraps to be wound about a specially roughened lower surface of the spindle itself, sometimes referred to as "bottomwinding", these yarn wraps serving to hold the ends of yarn in place on the spindle during doffing of the full bobbin whereby the yarn will break during doffing.
To facilitate this breaking of the yarn where the full bobbins are automatically doffed, the lower portion of the spindle is usually provided with an outwardly extending cutter edge configuration located just above the aforesaid roughened lower surface of the spindle upon which the yarn wraps are laid, and as the full bobbins are doffed from the spindles the yarn is tensioned across the cutter edge configuration and severed thereby; a typical spindle construction of the aforementioned type is disclosed in Winter U.S. Pat. No. 3,210,922.
It will be apparent that each time a bobbin is doffed from the spindle, a plurality of yarn wraps remain on the lower portion of the spindle, and these yarn wraps will accumulate, unless removed, as a number of doffing cycles are completed. Excessive accumulation of these yarn wraps can have serious adverse consequences. For example, if the accumulation of yarn wraps is uncontrolled, the build-up may increase the effective diameter of the lower portion of the spindle to a point that the yarn wraps extend outwardly beyond the diameter of the cutter edge configuration on the spindle whereby insufficient tension is imposed on the yarn across the cutter edge configuration, and the yarn may not be severed by the cutter edge configuration during doffing of the bobbin.
Accordingly, devices for cleaning the yarn wraps from spindles have heretofore been developed to overcome the aforementioned problems of uncontrolled yarn wrap accumulation. For example, Winter U.S. Pat. No. 3,426,518 and Jones U.S. Pat. No. 3,263,407 both disclose hand-operated yarn wrap cleaners designed to be selectively mounted on the spindle rail of a spinning frame for movement therealong, these cleaners including cleaning elements which engage the lower portions of the rotating spindles as the cleaners are manually pushed along the spindle rail. More sophisticated yarn wrap removal devices are disclosed in Schumann U.S. Pat. No. 3,312,051 and Keller U.S. Pat. No. 4,133,168 which provide carriage means adapted to be mounted on a rail extending along the spinning frame, this carriage means including spindle cleaning elements as well as suction apparatus to draw away the yarn wraps as they are separated from the spindle by the cleaning elements during movement of the cleaning devices along the spinning frame rail.
However, in manually operated yarn wrap cleaning devices, the labor costs are quite high and, frequently, the operating personnel do not clean the spindles as often as is necessary. As a result, the yarn wraps often accumulate to an extent that improper severing of the yarn results as described above, or to an extent that results in an excessive amount of "fly" being generated when the large accumulation of yarn wraps is eventually cleaned. In some cases, even the provision of suction apparatus with the yarn wrap cleaner will not draw away all of the "fly" because of its volume and tendency to be propagated, during removal, beyond the effective drawing power of the vacuum source. The resulting "fly" may create an unacceptable dust level in the spinning room, and may adhere to the yarn being processed so as to adversely affect the quality thereof. Thus, while the above-mentioned prior art yarn wrap cleaning devices may, if used after each doffing cycle, properly clean yarn wraps from the spindles, the labor costs required to use these devices and the difficulties required to mount the apparatus on the spinning frame often result, as a practical matter, in such equipment not being used frequently enough, thereby creating the accompanying disadvantages noted above.
Finally, in the aforementioned Schumann U.S. Pat. No. 3,312,051, there is disclosed, in FIG. 5 thereof, a permanently installed vacuum system having spindle scraping devices associated therewith which are moved horizontally into and out of engagement with the spindles by cams. While this arrangement avoids the necessity of mounting the cleaning unit on the spinning frame each time it is used, such arrangement is cumbersome and would be relatively expensive to produce and mount on existing spinning frames. Additionally, the spinning room personnel would bear the burden of operating the equipment at regular intervals to avoid an excessive accumulation of yarn wraps on the spindles.
To avoid the foregoing drawbacks of the prior art, the present invention provides simple, inexpensive apparatus for cleaning spindles, and such apparatus may be operated automatically by the ring rail of the spinning frame to effectuate cleaning of the spindles after each doffing cycle.